Ga. Bendrick et al., INFLIGHT OXYGEN-SATURATION DECREMENTS IN AEROMEDICAL EVACUATION PATIENTS, Aviation, space, and environmental medicine, 66(1), 1995, pp. 40-44
Past studies have shown that patients with severe chronic obstructive
pulmonary disease (COPD) may experience oxygen desaturation at the cab
in altitudes of pressurized aircraft. Because COPD can be associated i
n varying degrees with ischemic heart disease (IHD), and because the c
onsequences of hypoxia in such patients can be significant, the ground
and altitude pulse oximeter readings of 24 ambulatory aeromedical eva
cuation patients with known or suspected IHD were recorded. Written, i
nformed consent, as well as smoking history and respiratory spirometry
were obtained preflight. Results showed a mean saturation decrease of
5.5 percentage points (95% CI: 4.5-6.4). The mean cabin altitude wets
6900 ft (range: 2500-8100). No patients experienced clinical symptoms
. Of 24 patients, 3 were given supplemental oxygen when their Inflight
oximetry readings consistently read below 90%. Saturation decrease di
d not correlate specifically with age, smoking history, the FEV1/FVC r
atio, or the inflight cabin altitude, We conclude that ambulatory aero
medical evacuation patients with known or suspected IHD may demonstrat
e mild decreases in oxygen saturation which are not readily predicted
by age, smoking history, preflight spirometry, or inflight cabin altit
ude. Pulse oximetry compatible with aircraft electrical systems may pr
ovide useful inflight monitoring on such patients.